A Palestinian firefighter works during efforts to extinguish a fire at Gaza's main power plant(Reuters)

Five Palestinian militants have been killed by Israeli forces after attempting to infiltrate Israel via a Gaza tunnel.

A Givati infantry battalion opened fire on the five militants when they were spotted emerging from a tunnel in the southern Gaza Strip, according to newspaper Haaretz.

The Israeli military confirmed that no Israeli soliders were hurt in the incident and that a large arms cache was found in the tunnel after the infiltration attempt.

The sophisticated tunnel network, which runs from deep inside the Gaza Strip into both Israel and Egypt, has been used by Hamas militants to circumvent the Israeli blockade, smuggle a variety of goods into Gaza and attack IDF soldiers.

This week, five IDF troops were killed when four Gaza militants entered Israel via a tunnel and fired on an anti-tank missile at an IDF guard post.

Israeli Prime Minister Benjamin Netanyahu has said the Gaza ground and air offensive will continue until the threat from the tunnel network is stopped altogether.

The infiltration attempt came after Hamas rejected a Palestinian call from the West Bank for a 24-hour ceasefire in the Gaza Strip.

The secretary-general of the Palestine Liberation Organisation (PLO), Yasser Abed Rabbo, had earlier said the idea held both Hamas and Islamic Jihad support.

But Sami Abu Zuhri, a Hamas spokesman in Gaza, said the claim was false and "not related to the resistance" which "speaks for itself" in Gaza.

"When we get guarantees from the Zionists for an international mediation regarding a humanitarian pause, then we can consider it," he said.

According to Palestinian officials, 1,156 Palestinians have been killed in Israel's offensive so far. A further 6,700 have been wounded, with more than 215,000 displaced in the territory - most have fled to UN shelters.

The Israeli military has confirmed the loss of 53 soldiers while three civilians, one a foreign national, have been killed in the fighting.

Israel refused to comment on the Palestinian ceasefire proposal, despite reports that they had rejected the offer.